In the hog industry, it is common practice to move gilts and sows to a separate gestation building with individual stalls for each sow. It is well-known that the feeding program for breeding pigs has a major impact on performance, including farrowing rate, litter size, piglet weaning weight, and sow health. Productive sows that have increased litter size and heavier piglets require more energy from feed, particularly with their lower body fat levels and the accompanying reduced energy reserves. If feeding is inadequate, the sows muscle tissue and overall health can be adversely affected. Thus, the sow feeding programs need to meet the nutritional requirements at all stages of their lifetime reproductive cycles. Sow longevity is increased when the feeding program provides body growth and maintenance, while achieving high birth rates and weaning weights.
During gestation, feed is used to maintain and grow sow muscle tissue, replenish sow fat reserves lost during previous lactations, and growth of the fetal pigs. The gestation diets are designed to maximize the number of pigs per litter and optimize the piglet birth weight. The gestation diets also can minimize the wean-to-conception period, maximize sow feed intake during lactation, and optimize sow longevity and lifetime productivity. when properly fed, a sow will grow larger as she ages, but without getting too fat or too thin. Overweight sows create numerous problems, including higher feed costs due to more food consumption, smaller and less vigorous litters, reduced mobility, reduced milk production, and accidental crushing of piglets. Similarly, underweight sows also lose muscle tissue resulting in premature culling, and other health issues. The feed diets vary from gilt development to gestation to lactation to farrowing. While all of these feeding stages are important, the present invention is particularly directed towards efficient feeding strategies for gestating sows as an important management practice needed for optimum production of offspring, as well as maintaining the health and longevity of the sows.
The amount of feed supplied during specific phases of gestation can positively or negatively affect sow performance. Proper nutritional management of gestating sows includes feeding the correct nutrient levels to meet the sow's requirement during the different gestation phases. Failure to meet the nutritional needs of the sow may result in smaller litters, reduced piglet birth weight and vigor, lower milk production, an increase in the weaning to service interval, a reduction in conception rates, and a shortened reproductive lifespan. Modern sows, with a lean genotype and superior reproductive performance, have different management needs from their counterparts from a generation or two ago.
During gestation, the feeding program should allow the sows to regain any condition or body weight lost during lactation, and reaches her proper condition for subsequent farrowing. The feeding program should also avoid overfeeding, which causes gilts in gestation to have reduced feed intake during lactation, thus, loss of body condition, and extended time from wean to estrous, as well as lower second litter size.
Gilts are often fed ad lib from the time of selection until needed for first breeding. However, when the gilt is brought into the gestation barn, the change in the feeding system from community self-feeding to isolated gravity drop feeders is not always an easy transition for the gilt. The use of gestation stalls, with individual daily feeding, provides the greatest control over the feed intake of the sow, and is the most common method used by producers in the industry. The gestation stalls allow each gilt and sow to be fed to condition, resulting in reduction in feed cost and improved breeding performance.
While ad libitum feeding with self-feeders is known in the swine industry, such feeding has not been utilized in individual stall applications, particularly during gestation. In the United States, the most common feeding equipment in gestation barns is a separate hopper and gravity drop feed tube for each gestation stall. The hoppers are periodically filled with feed, which then falls to the stall floor where the sow can consume the feed, if she is hungry. Otherwise, residual feed is periodically washed from the trough. Thus, if the sow does not eat the feed when it is dropped from the tube, the feed is wasted, and can lead to clogging of the trough drainage system.
Accordingly, a primary objective of the present invention is a self-feeding device for sows and gilts in a gestation stall to maximize feeding strategy and management during gestation.
Another objective of the present invention is the provision of a device for converting a gravity drop feeder in a sow gestation pen to an ad lib feeder so as to maximize litter size and live births, piglet growth, weaning weight, and sow health and longevity.
A further objective of the present invention is a retrofit method of converting a conventional gestation stall drop feeder to a self-feeder for ad lib consumption by the sow.
Yet another objective of the present invention is the provision of a feed control plug or valve which can be quickly and easily installed in the open lower end of a feed drop tube in a swine stall.
Still another objective of the present invention is the provision of a self-feeding device for retrofit installation into a feed drop tube which is virtually maintenance free.
Another objective of the present invention is the provision of a self-feeding device in a gestation stall which is easy for the sow to learn and to actuate.
A further objective of the present invention is the provision of a retrofit self-feeding device for a gestation stall feeding system which is economical to manufacture, and durable and safe in use.
These and other objectives will become apparent from the following description of the invention.